A&p Vocab Ch. 5

Front 1

1. Cutaneous Membrane

Back 1

Covers the external surface of the body and is the largest organ of the body in both surface area and weight.

Front 2

2. Integument

Back 2

Covers the external surface of the body and is the largest organ of the body in both surface area and weight.

Front 3

3. Epidermis

Back 3

The superficial, thinner, portion, which is composed of epithelial tissue.

Front 4

4. Dermis

Back 4

The deeper, thicker connective tissue portion.

Front 5

5. Subcutaneous Layer

Back 5

Deep to the dermis, but not part of the skin.

Front 6

6. Hypodermis

Back 6

This layer consists of areolar and adipose tissue.

Front 7

7. Pacinian (lamallated) Corpiscles

Back 7

Nerve endings that are sensitive to pressure.

Front 8

8. Keratinocytes

Back 8

About 90% of the epidermal. Are arranged in four or five layers and produce the protein keratin.

Front 9

9. Keratin

Back 9

A tough, fibrous protein that helps protect the skin and underlying tissue from heat, microbes, and chemicals.

Front 10

10. Melanocytes

Back 10

About 8% of the epidermis. Develop from the ectoderm of a developing embryo and produce the pigment melanin.

Front 11

11. Melanin

Back 11

A yellow-red or brown-black pigment that contributes to skin color and absorbs damaging ultraviolet light.

Front 12

12. Langerhans Cells

Back 12

Arise from red bone marrow and migrate to the epidermis where they consitiute a small fraction of the epidermal cells. They participate in immune responses mounted against microbes that invade the skin, and are easily damaged by UV light.

Front 13

13. Merkel Cells

Back 13

The least numerous of the epithelial cells. They are located in the deepest layer of the epidermis, where they contact the flattened process of a sensory neuron.

Front 14

14. Merkel (tactile) Disc

Back 14

Sensory neuron. Detect touch sensations.

Front 15

15. Thin Skin

Back 15

In most regions of teh body the epidermis has four strata or layers- stratum basale, stratum spinosum, stratum grandulosum, and a thin stratum corneum.

Front 16

16. Thick Skin

Back 16

Where exposure to friction is greatest, such as in the fingertips, palms, and soles, the epidermis has five layers- stratum basale, stratum spinosum, stratum grandulosum, stratum lucidum, and a thick stratum corneum.

Front 17

17. Stratum Basale

Back 17

The deepest layer of the epidermis, composed of a single row of cuboidal or columnar kerationocytes.

Front 18

18. Stratum Germinativum

Back 18

The stratum basale is also know as this to indicate its role in forming new cells.

Front 19

19. Stratum Spinosum

Back 19

Superficial to the stratum basale. Arranged in 8 to 10 layers of many-sided keratinocytes fitting closely together.

Front 20

20. Stratum Granulosum

Back 20

At about the middle of the epidermis. Consists of 3-5 layers of flattened keratinocytes that are undergoing apoptosis.

Front 21

21. Keratohyalin

Back 21

A distinctive layer is the presence of darkly staining granules of a protein, which converts the tonofilaments into keratin.

Front 22

22. Lamellar Granules

Back 22

Release a lipid-rich secretion. This secretion fills the spaces between cells of the stratum granulosum, stratum lucidum, and stratum corneum.

Front 23

23. Stratum Lucidum

Back 23

Present only in the thick skin areas. It consists of 3-5 layers of flattened clear, dead keratinocytes that contain large amounts of keratin and thickened plasma membrane.

Front 24

24. Stratum Corneum

Back 24

Consists on average of 25-30 layers of flattened dead keratinocytes.

Front 25

25. Keratinization

Back 25

As the cells move from one epidermal layer to the next the accumulate more and more keratin.

Front 26

26. Papillary Region

Back 26

Makes up about one-fifth of the thickness of the total layer. It consists of areolar connective tissue containing thin collagen and fine elastic fibers.

Front 27

27. Dermal Papillae

Back 27

Small, fingerlike structures that project ito the undersurface on the epidermis.

Front 28

28. Capillary Loops

Back 28

Blood vessels.

Front 29

29. Meissner Corpuscles

Back 29

Nerve endings that are sensitive to touch.

Front 30

30. Free nerve Endings

Back 30

Dendrites that lack and apparent structural specialization.

Front 31

31. Reticular Region

Back 31

Is attached to the subcutaneous layer, consists of dense irregular connective tissue containing fibroblasts, buldles of collagen, and some coarse elastic fibers.

Front 32

32. Extensibility

Back 32

Ability to stretch.

Front 33

33. Elasticity

Back 33

Ability to return to original shape after stretching.

Front 34

34. Striae

Back 34

Stretch marks. Visible as red or silvery white streaks on the skin surface.

Front 35

35. Epidermal Ridges

Back 35

Produced during the third month of fetal development as downward projections of the epidermis into the dermis between the dermal papillae of the papillary region.

Front 36

36. Fingerprints

Back 36

Because the ducts of sweat glands open on the tops of the epidermal ridges as sweat pores, the sweat and ridges form these.

Front 37

37. Nevus (mole)

Back 37

A round, flat, or raised area that represents a benign localized overgrowth of melanocytes and usually develops in childhood or adolescence.

Front 38

38. Melanosome

Back 38

Synthesis occurs in an organelle called this.

Front 39

39. Hemoglobin

Back 39

The oxygen-carrying pigment in red blood cells.

Front 40

40. Carotene

Back 40

A yellow-orange pigment that gives egg yolk and carrots their color.

Front 41

41. Albinism

Back 41

The inherited inability of anindividual to produce melanin.

Front 42

42. Vitiligo

Back 42

The partial on complete loss of melanocytes from patches of skin produces irregular white spots.

Front 43

43. Hairs (pili)

Back 43

Are present on most skin surfaces except the palms or palmar surfaces of the fingers, the soles, and plantar surfaces of the feet.

Front 44

44. Shaft

Back 44

The superficial portion of the hair, which projects above the surface of the skin.

Front 45

45. Root

Back 45

The portion on the hair deep to the shaft that penetrates into the dermis, and sometimes into the subcutaneous layer.

Front 46

46. Hair follicle

Back 46

Surrounds the root oh the hair. Made up of an external root sheath and an internal root sheath.

Front 47

47. Epithelial Root Sheath

Back 47

Made up of an external root sheath and an internal root sheath, together called this.

Front 48

48. Dermal Root Sheath

Back 48

The dense dermis surrounding the hair follicle.

Front 49

49. Bulb

Back 49

The base of each hair follicle and its surrounding dermal root sheath is an onion-shaped structure.

Front 50

50. Hair Papilla

Back 50

Contains areolar connective tissue and many blood vessels that nourish the growing hair follicles.